Supporting results for pointwise provable equality.
Persistence for constructor 7 of the existing Mathlib-index history evaluator. The subsidiary-index premise is discharged by the external induction on indices; the same-index recursive lookup is handled by PA induction on the source stage.
theorem
PointwiseComposition.CategoricalRiceShapiro.Evaluator.evalnCertificateFormula_tag_seven_iff
{M : Type u_1}
[FFL.ORingStructure M]
[M↓[ℒₒᵣ] ⊧* 𝐏𝐀]
[M↓[ℒₒᵣ] ⊧* 𝐈𝐎𝐩𝐞𝐧]
(q : ℕ)
(hq : ArithmeticCode.partrecCodeTag q = 7)
(s u y : M)
(hs : 0 < s)
:
(FFL.FirstOrder.Semiformula.Evalb ![s, ↑q, u, y]) ↑evalnCertificateFormula ↔ u < s ∧ ∃ (x : M),
(FFL.FirstOrder.Semiformula.Evalb ![s, ↑(ArithmeticCode.partrecCodePayload q), u, x]) ↑evalnCertificateFormula ∧ (0 < x ∧ (FFL.FirstOrder.Semiformula.Evalb ![s - 1, ↑q, ⟪π₁ u, π₂ u + 1⟫, y]) ↑evalnCertificateFormula ∨ x = 0 ∧ y = π₂ u)
The complete tag-7 equation for the existing raw computation formula, valid at arbitrary stages and arguments of every model of PA.
theorem
PointwiseComposition.CategoricalRiceShapiro.Evaluator.evalnCertificateFormula_natCode_persist_of_tag_seven
{M : Type u_1}
[FFL.ORingStructure M]
[M↓[ℒₒᵣ] ⊧* 𝐏𝐀]
[M↓[ℒₒᵣ] ⊧* 𝐈𝐎𝐩𝐞𝐧]
(q : ℕ)
(hq : ArithmeticCode.partrecCodeTag q = 7)
(ih :
∀ p < q,
∀ (s t u y : M),
s ≤ t →
(FFL.FirstOrder.Semiformula.Evalb ![s, ↑p, u, y]) ↑evalnCertificateFormula →
(FFL.FirstOrder.Semiformula.Evalb ![t, ↑p, u, y]) ↑evalnCertificateFormula)
(s t u y : M)
:
s ≤ t →
(FFL.FirstOrder.Semiformula.Evalb ![s, ↑q, u, y]) ↑evalnCertificateFormula →
(FFL.FirstOrder.Semiformula.Evalb ![t, ↑q, u, y]) ↑evalnCertificateFormula
Constructor-7 persistence of the accepted computation formula. The only premise is persistence for strictly smaller standard program indices.